From 071786e27d81d3e8ae11f078357c9373fc4ce2e8 Mon Sep 17 00:00:00 2001 From: Kuen-Han Tsai Date: Wed, 15 Oct 2025 03:50:52 +0800 Subject: usb: core: Add tracepoints for device allocation and state changes Introduce new tracepoints to the USB core to improve debuggability of USB device lifecycle events. The following tracepoints are added: - usb_alloc_dev: Triggered when a new USB device structure is allocated, providing insights into early device setup. - usb_set_device_state: Triggered when the USB device state changes, allowing observation of the device's state transitions. These tracepoints capture detailed information about the USB device, including its name, speed, state, bus current value, and authorized flag. This will aid developers in diagnosing issues related to device enumeration within the USB subsystem. Examples: usb_alloc_dev: usb 1-1 speed UNKNOWN state attached 0mA [authorized] usb_set_device_state: usb 1-1 speed UNKNOWN state powered 0mA [authorized] usb_set_device_state: usb 1-1 speed full-speed state default 500mA [authorized] usb_set_device_state: usb 1-1 speed full-speed state default 500mA [authorized] usb_set_device_state: usb 1-1 speed full-speed state addressed 500mA [authorized] usb_set_device_state: usb 1-1 speed full-speed state configured 500mA [authorized] usb_set_device_state: usb 1-1 speed full-speed state suspended 500mA [authorized] usb_set_device_state: usb 1-1 speed full-speed state not attached 500mA [authorized] Signed-off-by: Kuen-Han Tsai Reviewed-by: Alan Stern Link: https://patch.msgid.link/20251015-usbcore-tracing-v2-2-5a14b5b9d4e0@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/trace.c | 6 ++++++ 1 file changed, 6 insertions(+) create mode 100644 drivers/usb/core/trace.c (limited to 'drivers/usb/core/trace.c') diff --git a/drivers/usb/core/trace.c b/drivers/usb/core/trace.c new file mode 100644 index 000000000000..607bcf639d27 --- /dev/null +++ b/drivers/usb/core/trace.c @@ -0,0 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2025 Google LLC + */ +#define CREATE_TRACE_POINTS +#include "trace.h" -- cgit